Receiving device for wireless systems.



W. E. D. STOKES, JR. & G. W. DAVIS. RECEIVING DEVICE FOR WIRELESSSYSTEMS.

APPLICATION FILED DEC. 9, 1908.

Patented M51113, 1914.

M v a Novice 1:31 at 4 e1 ass fsysteins ct wli' c1 ing is especification. e object o invention is to s new snd in red receivingdevice ior wireless telegraph or telephone systems.

those cys eniplefri what is known as the imperfect contest frequentadjustments here to he .con-

which often interrupts continuity with which the message can he endleeds to diiliculty in the service. To over come this objection, weprovide i system by which 2; large number contacts are pro vided, anyone of which instsntly he lbrought into circuit so. that if one contsctgives out or works imperfectly, another contact can he almostimmediately utilized. lhe contact element which we preferably employcomprises 2, particular lrind of? iron pyrites, such as is found innature in noncrystalline form and which has s, more or less carbonaceousshale enihedded therein. 'lo utilize these improvements, we preferablyarrange one or more elements of this material on it stand and arrange eplurality of contacts with the various faces of each element so thatdillerent portions of the some element can he used. "We also provideelectric switching mechanism so that any one of the contacts can hequickly thrown into circuit. By this arrangement, the contacts may headjusted to' various resistance and degrees of sensitiveness and anydesired contact can he quickly thrown into circuit without having tolose time by making adjustment when receiving messages.

Une embodiment of the invention is represented in the accompanyingdinning, re- 'lerring to which,

Figure l is e disgre-uimetic view illustinting" n wireless system withour invention applied thereto. Q is e plan view ol the contactarrangement on on enlarged scale, and 3 is e sectionnl View on the line3-3 on a still larger scnle.

designe es en ll ch the ground or can th in e A goes th insiornier or Jor which is circuit. in this cciving circuit we piece condenser or c cit} D which may he adjustable and iustnlile resistance or resists-nohotter may also he includ cnit. El telephone or other i receivingcircuit coining circuit is preferably provided with switch I by whichsaid circuit can he cut out when messages ere being or when thereceiving eiiciiit s not to he riser. Bridging the receiving circuit intassel manner is e responding circuit lll in which is pieced theimperfect contacts here insfter described. The circuit arrangementshereinbefore described are of an ordinary type and any other form orarrangement may he used.

The plurality 0t imperfect contacts is errange in the bridging circuit10ll as follows: 0n e suitable base of insulating insteriei 12 isarranged at series of posts 18 eech having an upwardly projecting stem14- which is screw-thrended- A piece of the element which is used whichis preferably iron pyrites of e non-crystalline form having embeddedtherein more or less carbonaceous shale, has a hole bored therethroughand is fitted or placed on the stem 14-. This element is represented byI? in the drawing and iorrns the imperfect contact. The same is rigidlyheld on the stem M by e thumb nut 15 threaded on said stein. Each post13 is connected by s wire 16 to a, common wire 1'? which is connected inthe circuit 10-ll. Surrounding each stand 13 is a plurality of stands oruprights l8, tour being shown in the drawing as surrounding each stand13. 'lhreeded'into each upright 18 is a, screw 19 which has a fine tip20 which may be inside 0t platinum or any desired material to con tnctwith the element P. Each of said screws 19 has an adjusting milled head23. and it check nut 22 is also threaded on the some. By thisarrangement, the contact or each point 20 with the element can heeccuretely end sensitivel adjusted and the adjustment one he fine bycheck nut 22.

Each of the stands or uprightslS is connected by a wire 23 to a buttonor post 24, which buttons or posts 24 are arranged in line near one sideof the base 12, as illustratcd in Fig. 2.

Brackets 25 are secured to the piece 12 and between said brackets isarranged a metallic rod 26. Sliding on this rod 26 is abiock 27 whichcarries a spring arm 28 which can contact with any one of the posts orbuttons 24. A screw 29 is threaded into the biock 2! so that the blockcan be locked in any position on the rod 26.

One of the brackets 25 is provided with a. binding post 30 to which thecircuit i0ll is connected. By this arrangement, any one of the contactscan he brought into the circuit ELL-ll by sliding the block 2? along therod 26 so that the spring arm 28 Wili contact with the proper button 2%.The contacts are adjusted at icisnre to obtain the desired resistanceandsensitiveness. Then when receivlng, if it found that any giarticniarContact is not Working accurately or as sensitireiy as desired, bysliding the block 27 along the rod 26, any one of the contacts can hetried and the one which is the mostresponsive can be left in thecircuit. can he done very quickly by the operator, as it requires noadjustment.

have found that is a peculiarity of erai contacts that the same havesome spots thereon which are more sensitive than others and that thereare nsnaiiy e plurality or" such snfaces around piece or mineral. Byerra: ging a oinraiity of contents around a. singie eiernent, advantagecan taken of this fact to get a number of contacts from one element.

We have found in practice that the iron pyrites of the characterdescribed makes a very sensitive and nice Working receiving orresponding element.

ihe details and arrangements herein shown and described. may be greatlyvaried by a. skilled electrician without departing from the scope of ourinvention as expressed in the claims.

iherefore having thus fuliy described our invention, What we chairs anddesire to secure by Letters-Patent is l. A receiver for Wireless systemshaving an element composed of iron pyrites having carbonaceous shaleembedded'therein.

2. A receiving arrangement for Wireiess systems, comprising a base, a.pinreiity of responsive elements carried thereby, stands or uprightsthereon supporting a piurality of adjustable contact-sengaging eachelement, 9. system of buttons or posts on said base connected with saidcontacts. a rod carried by said base, and e. sliding bloclr on said rodwhich can be moved to engage any one of said buttons or posts, wherebyany contact can be thrown. into circuit;

hereunto testimony whereof we have two sub- Witnesses:

Minnie: L. Beers INA it. BAGWELL.

